The danger of verticals is that people don't want to have to think about what site to visit depending on what they're looking for. Sure, it would improve relev

The danger of verticals is that people don't want to have to think about what site to visit depending on what they're looking for. Sure, it would improve relevance, but I think you'd find that the increased relevance isn't worth the inconvenience to the majority. That said, what people forget is that there are still many areas where Google is not the king of search, especially at the enterprise level, so even with Microsoft, Endeca, Autonomy, and other search companies, there's still room for competition.